Online reading is slower than reading on print: our eyes tend to scan and skip: from tempting phrase to annoying banner ad to intriguing picture. So I keep readers on the page using only what's available to me: words. I pace the content, I don't waste words, I don't mislead.
You have to write just enough to keep search engines happy. And people, happier. Think of a search result as a table contents. That's what's available. That's how "find-able" your site is.
But search engines, last time I looked, don't buy your products, sign up for your program trials, take part in your surveys, download your ebook, or email you for more information. People do.
And dull writing hardly persuades people to do more than leave your website.
Unique writes do.